The purported health benefits of natural spring waters date back millennia—everyone from the ancient Greeks, to the Celts and Romans believed in the curative properties of these hot baths. Today, a good steep in these gorgeous locales is known to reduce inflammation, relieve muscle and joint pain, and even treat burn patients.

Our favorite picks include Kusatsu Onsen, Japan (pictured) which receives 3 million visitors a year, and looks as serene as it is beautiful. Chena Hot Springs in Alaska offers a nice contrast to the surrounding freezing temps, while Reykjadalur in Iceland requires a literal hike to get to, but looks completely worth it.

If you want to hit multiple pools in one trip check out Budapest, which is known as the spa city, with its Szechenyi Bath taking the prize for the largest in Europe.

This list is definitely going to inspire some vacation planning, or at the very least, googling the nearest spa.